A variety of subcutaneously implantable access ports have been utilized by clinicians to deliver fluids to, and/or to withdraw fluids from, the blood stream or other subcutaneous cavities inside a patient. One example of such an access port includes a substantially needle-impenetrable housing, which encloses one or more fluid cavities and defines for each of such fluid cavity an access aperture communicating through the housing on the side thereof, which is adjacent to the skin of the patient when the access port is implanted in the body of a patient. A needle-penetrable septum is received in and seals the access aperture. An exit passageway located in a port stem communicates with the fluid cavity or cavities for dispensing medication therefrom to a predetermined location in the body of the patient through an implanted catheter attached to the access port. Typically, the catheter is connected to the access port by placement of the proximal end of the catheter over a port stem. A locking sleeve or ring may be placed over the catheter at the proximal region of the catheter to secure the catheter to the port stem.
Once the access port and catheter have been implanted beneath the skin of a patient, quantities of fluid, such as medication or blood, may be dispensed from the fluid cavity by means of a non-coring needle passed through the skin of the patient and penetrating the septum into the fluid cavity. This fluid may be directed to the distal end of the catheter to an entry point into the venous system of the body of the patient. Blood may also be withdrawn for sampling from the body of the patient through such an access port by piercing the skin of the patient and penetrating the septum with a non-coring needle and applying negative pressure thereto, which causes blood to be drawn through the catheter into the fluid cavity covered by the pierced septum and then out of the body of the patient through the needle. To prevent clotting thereafter, the withdrawal route may be flushed with a saline solution or heparin using again a non-coring needle piercing the skin of the patient and the septum in the same manner as if a medication were being infused.
Both intermittent and continual injections of medication may be dispensed by the access port. Continual access may involve the use of a non-coring needle attached to an ambulatory-type pump or gravity feed bag suspended above the patient. The ambulatory-type pump or the gravity feed bag continually delivers the medication or fluid through the needle to the fluid cavity in the access port and from there through the catheter to the entry point into the venous system.
The access port is generally implanted into a patient's body by creating a subcutaneous pocket and inserting the port, which is connected to a catheter. The access port is implanted just below the patient's skin so that it may be felt by a clinician prior to access with a needle. Typically, the access port is sutured into the subcutaneous pocket to prevent migration thereof as well as to ensure that the port does not turn over such that the septum is not accessible, either of which occurrence would require further surgery. Suturing of the access port requires that the subcutaneous pocket be sized large enough to allow the surgeon to operate and is somewhat time consuming. Usually, the suturing of the access port occurs only on the most-accessible side thereof after insertion into the subcutaneous pocket, meaning that at least one side of the access port is left unsecured. Moreover, the act of suturing carries with it the inherent risks of needle sticks to the operating surgeon. With respect to the patient, the use of sutures (as opposed to a device that does not require the use of sutures) means that removal of the access port is more time consuming for the surgeon and more traumatic for the patient. Further, as the size of the subcutaneous pocket is increased because of the need to utilize sutures, healing time, blood loss, scarring and infection likelihood are increased.
Applicant recognizes the desirability of providing an access port, which does not require sutures for implantation within the body of a patient, which provides a smooth exterior surface prior to implantation for facilitation thereof, and which has an integral attachment mechanism that can be activated following insertion into the subcutaneous pocket such that it can safely be implanted and removed without exposing the clinician to sharp surfaces.